Misoprostol vaginal delivery system (Mysodelle): reports of excessive uterine contractions (tachysystole) unresponsive to tocolytic treatment

Monitor patients closely and remove the vaginal delivery system immediately in cases of excessive or prolonged uterine contractions, at the onset of labour, or if there is clinical concern for mother or baby.

• From: Medicines and Healthcare products Regulatory Agency
• Published: 6 February 2018

• Therapeutic area: Obstetrics, gynaecology and fertility

Advice for healthcare professionals:

• Mysodelle can cause uterine tachysystole that may not respond to tocolytic treatment
• monitor patients closely and remove the vaginal delivery system immediately if any of the following apply:
  • tachysystole: more than 5 contractions in a 10-minute window, averaged over a 30-minute window
  • prolonged contractions: single contractions lasting 2 minutes or longer
  • hypertonic contractions: contractions that are too frequent and a high resting tone in the uterus
• also remove the vaginal delivery system in the following instances:
  • there is a clinical concern for the mother or baby
  • onset of labour: rhythmic, firm contractions of adequate quality associated with cervical change, and/or at the latest when cervical dilation is 4 cm
  • when 24 hours have elapsed since insertion
• be prepared to administer tocolytic therapy; should this be needed, it can be administered immediately after removal of Mysodelle

Risk of tachysystole

Misoprostol (Mysodelle) vaginal delivery system is authorised for induction of labour in women with an unfavourable cervix, from 36 weeks’ gestation, in whom induction is clinically indicated.

A routine EU review of Mysodelle investigated reports from a study^{[footnote 1]} in which 13% of women (90 of 678 patients) randomly assigned to the 200-mcg misoprostol vaginal insert developed uterine tachysystole requiring intervention. In 5 cases (0.7% of women), uterine tachysystole did not subside with the use of tocolysis.^{[footnote 1]}

Uterine tachysystole has been associated with poor uterine placental perfusion leading to a decrease in foetal oxygenation and eventually foetal compromise. In the study, despite the higher incidence of tachysystole requiring intervention recorded in women given the misoprostol vaginal insert than those given a dinoprostone vaginal insert (13% versus 4%, respectively), neonatal outcomes did not appear to differ.^{[footnote 1]}

The EU routine review of these cases concluded that uterine tachysystole that may not respond to tocolytic treatment can be caused by Mysodelle, even when used in accordance with the product information. The product information for Mysodelle has been updated to reflect this finding, and with actions to take to ensure that this risk is adequately managed. A letter was also sent to alert relevant healthcare professionals.

Call for reporting

Please continue to report suspected adverse drug reactions to misoprostol on a Yellow Card.

Further information

Mysodelle. Summary of Product Characteristics (SPC).

Direct Healthcare Professional Communication. Misoprostol vaginal delivery system (Mysodelle). 8 January 2018

Article citation: Drug Safety Update volume 11 issue 7; February 2018: 1.

Post-publication note.

On 12 February 2018, the dose of Mysodelle used in the study was corrected from 200 mg to 200 mcg.

1. Wing DA, et al. Misoprostol vaginal insert and time to vaginal delivery: a randomized controlled trial. Obstet Gynecol 2013; 122: 201–09. ↩ ↩² ↩³

Published 6 February 2018